Fuze for rocket projectiles



May 15, 1962 R. APOTHELOZ ET .5L 3,034,438

FUZE FOR ROCKET PROJECTILES f1 PoTHLoz Hansrueli DUBACH INVENTORS May 15, 1962 R. APoTHELoz ET AL 3,034,438

FUzE FOR ROCKET PRoJEcTILEs Filed March 23. 1959 4 Sheets-Sheet 2 Fig.6 Fig. 8

Robert APoT'H ELoz HansrumQ DUBACH INVENTORS May 15, 1962 R. APoTHELoz ET AL 3,034,438

FUZE FOR ROCKET lPROJ1-3CTILES Filed Marci 23, 1959 I 4 sheets-sheet s Raben' APoTHE'LoZ HM wel; DUBACH I-NvEHToRs May 15, 1962 R. APOTHELOZ ETA. 3,034,438

FUzE FOR ROCKET PROJECTILES v Filed March 25, 1959 4 sheets-sheet 4' Hc 3 'L /.9.1328 a /l lla 14e fil H Robesr APoTHLoz al: WM@ grml NJW- Patented Mayl, 1962 3,034,43 FUZE FR RQCKET PROJECTILES Robert Apothloz, Walliseilen, Zurich, and Hansruedi Durbach, Zurich, Switzerland, assignors to Machine Tool Works Oerlikon, Administration Company, Zurich- ()erlikon, Switzerland, a company of Switzerland Filed Mar. 23, 1959, Ser. No. 801,222 Claims priority, application Switzerland Mar. 28, 19%

I Claims. (Cl. 102-78) The present invention relates to a fuze for rocket projectiles having a detonator carrier arranged in a recess of the fuze body which carrier is subject to the action of a spring and can be moved from a transport position in which the detonator lies outside the path of the detonating means into a cocked position in which it lies in the path of the detonating means, and having a longitudinally movable inertia body, the relative movement of which after the firing is used for cocking t-hc detonator carrier. l

In a known fuze of this kind the detonator carrier is a rotor rotatable about an axis transverse of the fuze axis, this carrier being turned into the cocked position by a toothed rack in driving connection with the inertia body and in mesh with -a gear pinion mounted on the rotor axle'. This fuze is designed for ordinary non-guided rockets and is cocked during the burning period of the propulsive charge i.e. during the acceleration phase of the rocket.

Such a fuze is unsuitable for example for remote-controlled anti-tank rockets. Such controlled rockets are well known to be steered to the target by the gunner by operating a control device, the steering impulses being transmitted to the rocket either by wireless or through wires connected with it. In order that the rockets may be safely steered to the target, their speed must not be more than a fraction of that of non-guided rockets. The steered rockets attain their maximum speed approximately in the same time as non-guided rockets of the same caliber, but owing to their lower speed they require a multiple of this time for covering a flight distance on which the fuze must not yet be cocked. This distance called also the trajectory safety distance of the rockets, has to be large in View of this possibility of a steering error committed by the gunner during the starting phase and the consequential danger of an impact of the rocket in the vicinity of the firing point. The cooking of the fuze for such steered rockets has accordingly to be effected mainly during the period in which the projectile flies towards the target without beingr subject to an acceleration. I

The present invention has the principal object of providing a fuze for rocket projectiles of t-he kind referred to which is suitable both for steered and nonguided projectiles. With this and other objects in View, which will become apparent later from this specification and accompanying drawings, we provide a fuze for rocket vprojectiles comprising in combination: a fuze body, a spring-biased detonator carrier having two abutment faces movable within the said fuze body, a detonator mounted in the said detonator carrier, a detonating means in operative relationship with the Said detonator, the said detonator carrier having a transport position in which the said detonator is offset from the said detonating means, a cocked position in which the said detonator is in juxtaposition withV the said detonating means, and an intermediate position, an inertia body longitudinally movable in the said fuze body locking the said detonator carrier in the transport position and by its movement relative to the saidV fuze body upon ring the rocket projectile leading to the unlocking of the said detonator carrier, a spring biased safety body longitudinally movable relative to the said inertia body and in driving connection therewith, an escapement operatively connected with the said safety body in the sense of slowing down its relative movements, the said safety body forming the path for the said detonating means and co-operating with the said two abutment faces of the detonator carrier, releasing during its retrograde movement the first one of these abutment faces and thereby allowing the said detonator carrier to be biased into the said intermediate position in which its second abutment face abuts the said safety body, the latter clearing this second abutment face at the end of its forward movement and thereby allowing said detonator carrier to proceed -to its cocked position. The said safety body has a ange-like enlargement.

The said detonating means may be a striker pin slidably mounted in a central bore of the said safety body and penetrating into the said detonator upon impact of the fuze when in the said cocked position. A nose may be provided on the saidfdetonator carrier and forming the said rst abutment face, the said two abutment faces bounding a recess provided in the said detonator carrier and lying one behind the other in the direction of movement of the said detonator carrier from the transport position -to the cocked position, the said nose being undercut by a groove allowing the said detonator carrier to move along the Said safety body occupying its rear position and beyond the said enlargement thereof.

These and other features of our said invention will be clearly understood from the following description of some embodiments thereof, given by way of example withreference to the accompanying drawings, in which:

FIGURE 1 is a longitudinal section of a fuze, in the transport position, serving as a safety element, for the warhead illustrated in FIGURE 5,

FIGURE 2 is a cross section on lthe line II-II of FIG- URE 1,

FIGURE 3 is a cross section on the line III-III of FIGURE 1, Y

FIGURE 4 is a part-section on the line IV-IV of FIG- URE 3,

FIGURE 5 is a longitudinal section, on a smaller scale, of the warhead of a rocket.

FIGURE 6 shows a fuze according to FIGURE l, partly in elevation and partly in section, in the position after the releasing of the rotor,

FIGURE 7 is a section on the line VII-VII of FIG- URE 6,

FIGURE 8 is a View corresponding to FIGURE 6 showing the fuze in the cocked position thereof,

FIGURE 9 is a longitudinal section of a fuze designed as an impact fuze, for example for the warhead according to FIGURES,

FIGURES l0 and 1l Show a further embodiment of the detonator carrier, namely FIGURE 10 a sectional plan View thereof, and

FIGURE l1 a section on thev line XI-XI of FIGURE 10,

FIGURE l2 is another section on the line III-III of FIGURE 1 in a different position,

FIGURE 13 is a section on the line XIII-XIII of- FIG- URE 12.

AAccording to FIGURE 1 the fuze casing denoted 1 isY -screwed to the fuze body 2, into which the casing cover 3 is screwed. In the bottom of the fuze casing the vbooster charge 4 is contained. Between the face 5a of the recess S, which is machined into the fuze body 2 perpendicularV to the fuze axis, and the booster charge 4 the detonating train 6 is inserted. The detonator carrier 7 designed as a rotor is arranged in the recess 5 and is rotatably mounted on the axle 9 xed to the fuze body 2 which axle is offset from and parallel to the fuze axis. The ends of the torsion spring 8 arranged in the interior of the rotor 7 abut the same and the axle 9, respectively.

The cylindrical rear part of the rotor 7 contains the detonator 10 in a bore running parallel to the axis of rotation and going right through. Diametrically opposite thereof lies a recess 7a which is bounded by faces 7b, 7c parallel to the axis. This recess is closed at the rear by a plate 7d. The forward part of the rotor 'is fitted co-axially to the rear part. The two cylindrical and coaxial circumferential surfaces 7e, 7Jc of the forward part have different radii measured from the rotor axis which are smaller than the radius of the rear part, and are joined to one another by two circular surfaces 7g, 7h (FIGURE 3). The surface 7h has the axis of the detonator 10 as its centre. With the straight face 7b, 7c cylindrical surfaces 7i, 7k are joined up, whose portions 7g and 7n leading into the forward position form a nose 7p. This nose 7p is undercut by a groove and is bounded at the rear by the face 7q. The surfaces 7i, 7k of the rear part of the rotor are joined to one another by a cylindrical surface 7l the radius of which measured from the rotor axis is equal to that of the surface 7e of the forward part of the rotor.

In the casing cover 3, which is open towards the fuze body, the cylindrical inertia body 11 is guided longitudinally movable. It is provided with a central longitudinal groove 11a which is closed on top by a bored cover 11b. The safety body 12 is formed by the two sleeves 13 and 14. The sleeve 13 is mounted slidably in the sleeve 14 and is biased against the shoulder 14b of the bore by a strong spring 15 abutting the shoulder 14a of the bore. By a rectangular ange extension 14C the sleeve 14 is guided longitudinally slidable in the groove 11a of the inertia body, co-axially to the fuze axis. Between the flange 14C and the extension 2a of the fuze body the spring 16 is built in. The rear end of the sleeve 14, provided with the flange 14d, projects into the recess 5 of the fuze body, while the toothed rack 14e is xedly connected with the forward end of this sleeve. According to the FIGURES l and 2 an escapernent is arranged in the groove 11d of the inertia body. This mechanism consists, apart from the oscillator body of a gear pinion 17 in mesh with the toothed rack 14e and of the toothed gears 18 to 25, which transmit the movement of the toothed rack 14e to the gear 26 having pointed teeth, and thereby to the oscillator body 27. The gear wheels and the brake vane body are journalled on axles mounted in the frame 28.

From this arrangement the following manner of functioning of the fuze results.

The fuze illustrated in the FIGURES 1 to 8 is designed as a safety element for the warhead illustrated in FIGURE of a rocket 29. In the tip of the warhead an impact fuze 3G is built in which contains the primary detonator 30a, while in the rear end the safety element S containing the secondary detonator 1i) is screwed-in in such a manner that it projects into the hollow charge 31.

In the transport position the components of the fuze are in the positions illustrated in the FIGURES l to 4. By the loaded torsion spring 8 the rotor 7 is held with its face 7n serving as an abutment against the flange 14d of the safety body 12, and the detonator is kept outside the range of the fuze axis and of the detonating train 6. Moreover the detonating train is covered by the plate 7d of the rotor. Consequently neither a spontaneous ignition of the secondary detonator which may be induced by shaking nor an impinging ame from the primary detonator in the fuze 30 can be transmitted through the detonat ing train 6 and the booster charge 4 to the hollow charge 31. The inertia body 11 is kept in the forward end position by the safety body 12 subject to the action of the spring 16 (FIGURE l).

During the acceleration period when firing the rocket projectile the inertia body 11 moves back owing to its inertia, pushing the sleeve 13 and thereby the safety body 12 rearward and loading the spring 16. By the retrograde movement of the toothed rack 14e connected to the safety body the escapement is driven through the i.. ti E gear pinion 17, and thereby the movement of the inertia body and of the safety body is braked. Shortly before reaching the rearmost position, the forward edge of the ange 14d of the safety body slides behind the face 7g of the nose 7p lying transversely of the rotor axis. The rotor is thereby freed and can now rotate inthe anticlockwise direction, the face 7l moving along under the face 7c; on the flange 14d. The rotational vmovement of the rotor is interrupted, when itsface 7b abuts the flange 14d of the safety body (FIGURES 6, 7). When no accelcrating force acts any more on the rocket and the safety body has reached its rearmost position, it is moved forward again together with the inertia body 11, by the action of 'the spring 16, in a movement braked by the escapernent, the rotor remaining preliminarily secured against further rotation. Only when the rocket projectile has covered the trajectory safety distance, i.e. when the rear face of the flange 14d has got beyond the forward edge 7r of the rear part of the rotor, the rotor can turn so far that the face 7/1 of the forward part abuts the ange 14d and consequently the detonator 10 is aligned co-axially with the axis of the safety body 12 and the detonating train 6. The fuze is then cocked (FIG- URE 8).

When the impact fuze 30 in the tip of the warhead of the rocket responds to hitting an obstacle, the irnpinging ame emitted rearward by the primary detonator is passed through the co-axial bores 3a, 11e, 13a and 1.4i lying one behind the other to the secondary detonator 1G in the safety element and the same is ignited, whereby the detonation of the hollow charge 31 s initiated through the detonating train 6 and the booster charge 4.

Jerks occurring on transport or when handling the rocket, which cause a rearward movement of the inertia body, are elfective only over very short periods. Owing to the braking action of the escapement the inertia body with the safety Ibody i12 will then move rearward but very little and then `return -to the starting position. Only when, upon tiring, the acceleration lasts over a longer period, the safety body can move back, las described hereinabove, to such an extent that the rotor is released and the fuze is cocked.

By the spring 15 interposed between the two sleeves 13 and 14 of the safety body 12 these jerks transmitted from the inertia body 11 to the sleeve 13 are strongly damped when being passed on to the Sleeve 14, and thereby the escapement is saved.

The fuze described hereinabove is developed according to FIGURE 9 as an impact fuze which is built into the tip of a rocket projectile. The difference as compared with thel rst embodiment of the fuze consists only in that a striker pin 35, arranged in the fuze axis is used as the detonating means instead of the impingng ame of a primary detonaton This striker pin is subject to the bias of the spring 36 and by the latter is forced with its shoulder 35a against a ring 38 fixed in the upper part 37 of the fuze casing. The cylindrical head 35h of the striker pin projects from the fuze casing and is covered by a cap 39 made of resilient material. The striker pin is guided in the bores 37a `and 37b of the fuze casing and projects with its stem 35C into the sleeves 13 and 14 of the safety body 12, wherein it is freely movable.

After the rotor has been released upon firing in the manner described and turned into the cocked position, the striker pin may upon impact of the projectile penetrate into the detonator 10 by its rearward movement, and thereby initiate the detonation of the explosive charge of the projectile.

In the FIGURES 10 and 1l a second embodiment of the detonator carrier is illustrated. According to these figures the same is designed as a slide movable transversely of the fuze axis, and is guided in a track 30a of rectangular prole penetrating transversely the fuze body 30. Transversely of the longitudinal axis of this track a slot 3019 is machined into the fur/.e body wherein a leaf spring 32 is contained which serves for the drive of the slide 33 and abuts the sleeve 31 pushed over the fuze body. Abutment faces I33a and 33h are formed bytwo bores lrunning parallel to the fuze 'axis which partly over-4 lap one another and the centres of which lie behind one another in the direction of movement of the slide. The groove 3-3f on the rear face of the slide forms a communication between thesaid two bores. The diameter of the ange 14d of the safety body corresponds to the width of the groove 33f but exceeds the spacing of the noses 33g between the said two bores. The groove 33] is higher than the flange 14d, but the diameter of the part of the sleeve 14 adjoining the same forwardly is slightly smaller than the said distance of the noses 33g. The face 33C forms the bottom of a groove 33e machined into the slide from its front and reaching from the abutment face 3327 up to its end, which groove is at least as wide as the diameter of the flange 14d.

Prom this design of the detonator carrier as a slide results a manner of operation of the fuze, which is identical to a far reaching extent with that described hereinabove: The safety lbody 12 holds with its ange 14d the spring-biased slide 33 in the transport position illustrated in FlGURE 1l. After the firing the flange 14d slides behind the abutment face 33a into the groove 33,1, whereafter the spring 312 can move the slide towards the left, until the safety body abuts the flange 33h. After this face has been released by the flange 14d of the advancing safety body the slide is completely pushed into the cocked position, which is attained when the detonator 34 is aligned co-axially with the safety 'body 12 and when the end face 33h of the slide abuts the sleeve 31.

With the embodiment of the invention described hereinabove of the detonator carriers 7 Iand 33 and of the safety body i2, trajectory safety distances of any desired length can be attained. With a given height of the detonator carrier the trajectory safety distance may for example be increased in that the escapement is modified in the sense of an amplified action. This brings about a shortening of the path covered by the safety body during the acceleration phase of the rocket. This is taken into account in that the safety body is retained before the tiring in a position lying further back from the ,detonator carrier, the forward face of the flange 14d abutting a locking face 7m of the fuze body under the bias of a spring 16, as illustrated for example in FIGURES l2 and 13. This locking face 7m is directed transversely of the abutment face 7n and bounds the same in the forward direction. In this arrangement, which obviously can be applied also to the detonator carrier designed as a slide according to FIGURES l0 and 1l, the inertia body 11 is not forced right up to the foremost position illustrated in FIGURE l, but only to the intermediate position illustrated in FIGURE 12. In accordance with the trajectory safety distance desired of the rocket the abutment face 7b (FEGURES 3, 6 and 7) may then be made so high that it is released yby the ange of the safety body shortly before it reaches its foremost position which lies ahead of the starting position prior to the firing.

While we have described herein and illustrated in the accompanying drawings what may be considered typical and particularly useful embodiments of our said invention, we wish it to be understood, that we do not limit ourselves to the particular details and dimensions described and illustrated; for obvious modifications will occur to a person skilled in the art.

What we claim as our invention and desire to secure by Letters Patent, is: v

l. A fuze for rocket projectiles comprising in combination a fuze body having a longitudinal axis, a first spring means, an arming member movable Within said fuze body by said first spring means from an initial transport position to an intermediate position and then to a cocked position, a detonator, detonating means for firing said detonator when said arming member is in said cocked position, a second spring means, control means for indexing said arming member, said control means being longitudinally mov-able within said fuze body and being loaded by said second spring means to perform responsive to setback a rearward movement yfrom a starting position to a second position, and to perform after termination of the setback a forward movement under the pressure of said second spring means towards said starting position, said arming member comprising a first face abutting in said transport lposition of said arming member said control means in said starting position and being disengageable from said control means upon the rearward movement of the latter to index said arming member from said transport position -to said intermediate position, a second face abutting in said intermediate position of said arming member said control means in said second position and being disengageable from said latter means upon the forward movement of said control means'to index said armingmember from said intermediate position to said cocked position. Y

2. A fuze for rocket projectiles comprising in combination a fnze body having a longitudinal axis, a first spring means, an arming member movable within said fuze body by said first spring means from an initial transport position to a cockedposition, retarding means supported in said fuze body, control means for controlling the movement of said arming member, said control means being longitudinally movable within said fuze body and comprising an inertia body, a safety body longitudinally Y movable on said inertia body, and driving means integral with said safety body `and in driving connection with saidV retarding means for braking the movement of said control means, auxiliary spring means interposed between said inertia body and said safety body, said anxiliary spring means biasingY said safety body and said inertia body in opposite directions for damping jerks' `transmitted from the inertia `body to the safety body.

3. A fuze for rocket projectiles comprising in combination a fuze body having'a longitudinal axis, a first spring means, an arming member movable within said fuze body by said first spring means from an initial transport position to an intermediate position and then -to a cocked position, a detonator, detonating-means for tiring said detonator when said arming member is in said cocked position, retarding means supported in said fuze body, a second spring means, a control means for indexing said arming member, said control means being longitudinally movable within said fuze body and being loaded by said second spring means to perform responsive to setback a rearward movement from a starting position to a second position, and to perform after termination of the setback a forward movement under the pressure of said second spring means towards said startfing position, said control means comprising an inertia body, a safety body longitudinally movable on said iny Y rections for damping jerks transmitted from the inertia'- body to the safety body, said arming member comprising a first face abutting in said transport position of said arming member said control means in said starting posil tion and being disengageable from said control means upon the rearward movement of the latter to index the said arming member lfrom said transport position to said intermediate position, a second face abutting in said intermediate position of said arming member said conl means has a longitudinal bore forming the path for said Y detonating means to said detonator.

5. A fuze as claimed in claim 4 wherein said detonating means is a striker pin slidably mounted in said longitudinal bore and penetrating into said detonator upon impact of said fuze when said arming slide is in said cocked position.

`6. A fuze as claimed in claim 1 wherein said control means comprises a ange-like enlargement for said in deXing of said arming member and in which fuze said arming member comprises a nose forming said first abutment face, said 4two abutment faces cooperating with said enlargement and lying in a staggered position one behind the other in the direction of movement of said arming member from said transport position to said cocked position, said nose being undercut by a groove form-ing a passage for said enlargement to enable said arming member to take said intermediate position after said rearward movement of said control means.

7. A fuze as claimed in claim 6 wherein said arming member comprises a third face directed transversely of said first abutment face limiting the same in -forward direction, and abutting in said transport position of said `arming member said enlargement foidetermining said starting position of said control means.

8. A fuze as claimed `in claim 1, wherein said control means has a fore-end, said fuze body comprising an abutment face abutting said fore-end infsaid starting position of -said control means.

9. A fuze as claimed in claim 1, wherein said arming member is rotatably supported round an axis parallel to said longitudinal axis `in said fuze body, and carries said detonator. 15 i 10. A fuze as claimed in claim 1 wherein said arming member is shi-ftably supported in said fuze body in a direction ,transverse to said movements of said control means, and carries said detonator.

References Cited in the tile of this patent UNITED STATES PATENTS 2,685,253 Apotheloz Aug. 3, 1954 2,836,118 Hjelm May 27, 1958 2,872,868 Donahue Feb. l0, 1959 2,873,681 Lauri-tsen Feb. 17, 1959 

